Various improvements including line numbers

[feelingsoflight]

I wasn't sure how interested you are in all changes, or even how to reach out to inquire [guess I could message you on reddit] but here's everything I've done. List is from memory. It also includes various things that might be personal preferences and/or deviate from the "just basic notepad"

• Make Ctrl+W close the app (in addition to Alt+F4)
• if you specify a non-existent file on the command line it will still load a non-existant file and create that file on save
  • this is commit b4f8426 but haven't tested it in isolation so you could look to extracting it idk
• Introduce "View | Line Numbers" (on by default) where it paints on left-hand gutter the line numbers of files
• Enable GoTo Line Number when word wrap is true
  • Will correctly navigate to file line even if word wrap is causing that to be weird
• Made word wrap off by default

This PR includes all other PRs I submitted - so if you merge this one it has all other enhancements. If this isn't of interest feel free to close/reject

Definitely use AI to assist so up to you. My goal was to get a notepad I could use for editing git commits and that kinda thing and load fast. Figured contributing back a few PRs was the least I could do